This is a renewal application for the continuation of a successful, multi-disciplinary Research Training Program that has been in place for more than 27 years in the Cecil H. and Ida Green Center for Reproductive Biology Sciences. Senior investigators with diverse backgrounds and areas of scientific expertness are enjoined to provide training in a number of areas of reproductive biology. The Green Center is an academic unit that is closely aligned with the Department of Obstetrics and Gynecology. Investigators from the Departments of Obstetrics and Gynecology, Pediatrics, Biochemistry, Cell Biology-Neuroscience, Microbiology, and Physiology participate in this training program. Basic Scientists (biochemists-molecular biologists, physiologists, immunologists, microbiologists, cell biologists, and pharmacologists) and clinical scientists (obstetricians and gynecologists specializing in endocrinology, oncology, and maternal-fetal medicine and pediatricians specializing in perinatal medicine) work side-by-side in contiguous, well-equipped, modern laboratory spaces. This is a unique environment and atmosphere for the training of postdoctoral and predoctoral students. For 27 years, a similar number of M.D. and Ph.D. postdoctoral trainees, who also work side-by-side, has been maintained in this Training Program. Each of the research faculty applicants is funded by grants from the National Institute of Health as principal investigators for one or more research projects. Each of the research faculty spend more than 85 percent of their time in the conduct of research, research- related endeavors (preparations of grant applications, manuscript and abstract preparation), and other research training activities. Several of the primary research training faculty of the Center are appointed to more than one academic department, I.e., Biochemistry, Cell Biology- Neuroscience, or Pediatrics and Obstetrics and Gynecology. Nine of the primary faculty also are members of the faculty of University of Texas Southwestern Graduate School of Biomedical Sciences and participate in 5 graduate programs, viz., Cell Regulation, Biochemistry and Molecular Biology, Immunology, Integrative Biology, and Molecular Microbiology. On average, there are 27 postdoctoral trainees and 5 predoctoral students conducting research in reproductive biology in the laboratories of the participating investigators and the Green Center. Each of the trainees is supervised by one or more of the senior faculty; and in all cases, the primary or secondary mentor of the M.D. trainees is a senior basic scientist. We (20 participating faculty) make application for support of 10 postdoctoral trainees (5 Ph.D. and 5 M.D. trainees, on average) and 2 predoctoral students matriculating for the Ph.D. degree. During the past 10 years, 45 postdoctoral and predoctoral trainees have been supported by this grant.